Functions of the Skull Bones – Living creatures such as humans and animals must have an anatomical body in which there is an arrangement of skeletons or bones that make up their body shape. In animals, they have a different form of skeletal structure depending on the type of animal, while in humans, everything tends to be the same, only maybe the size is different.
One of the bones that we will discuss in this discussion is the skull bone. Every bone in the body has its own function which is very important to protect the organs in the body which are then covered with skin. The skull bones have a function to protect the inside of the head such as the brain from collisions and form the human face to be different from other humans.
Even though the skull bones seem simple, you need to know that there are many parts of the bones that make up the skull bones to form a unified whole in the human head.
For this reason, for Sinaumed’s friends who want to know more about what are the parts of the skull and their functional role in the human head, in this discussion we have summarized various information related to the skull bones which can be additional knowledge for all of you Sinaumed’s friends.
Furthermore, we will present information about the functions and parts of the skull bones below!
Definition of Skull Bones
The skull is a bony structure in living things which is the skeleton of the head. The skull supports the structure of the head and protects the body from injury. In addition to protecting the brain, the skull provides sufficient distance between the eyes for stereoscopic vision and houses the ears so that the brain can determine the direction and distance of sound.
There are several differences between human and animal skulls, animal skulls can have horns which are important for self-defense. Whereas in humans, the adult skull usually consists of 22 bones. The skull (calvaria or calva) is made up of about 29 bones that normally protect or support the function of the organs of the head and face. The subsequent division of the skull into groups often varies depending on the reference source.
Functions of the Skull Bones and Their Parts
The skull composes the head and face while protecting the brain. The cranial bones can be divided into cranial bones which form the skull, and facial bones which form the face. The main function of the skull is to protect the brain, including the cerebrum, cerebellum, and brainstem. The skull also provides a surface on which facial muscles can attach.
The skull bones are not involved in any bodily movement or activity. The skull bones consist of two groups of constituent bones, the cranial bones and the facial bones. In the head, the skull bones are divided into eight categories. Some are flat, some are irregular, so they are called irregular bones. In more detail, these are the types of cranial bones that are part of the head or skull:
1. Frontal Bone (Front)
The frontal or front bone, precisely on the forehead, supports the front and back of the skull. The outside of this bone structure is flat and the inside is concave. The main function of the frontal spine is to protect the brain and support structures of the head, such as the nasal cavities and eyes.
2. Parietal Bone (Upper Bone)
The parietal bones are located at the top of the head or are called the fontanel, which are a pair of flat bones located on both sides of the head, behind the frontal bone. This bone is often referred to as the fontanel.
3. Temporal Bones (Temple Bones)
The temporal bones are precisely the bones that are in the temples located under each parietal bone. These bones are a pair of irregularly shaped bones that surround the middle and inner ear. The lower part is connected to the jaw to help the mouth open and close.
The temporal bones contribute to the structure of the skull and protect the brain and the membranes that surround it. This bone is also connected to several important muscles, such as muscles that help chew and swallow and muscles that move the neck and head.
4. Occipital bone (back of the head)
The occipital bone is a flat trapezoid bone located at the back of the skull. This bone has a hole that serves as a link between the spinal cord and the brain.
Specifically, the occipital bone protects the part of the brain that processes vision. In addition, this bone also plays a role in body movement, balance, and the ability to see and interact.
5. Sphenoid Bone (Wedge Bone)
The sphenoid bone or wedge consists of an irregular bone in the center of the skull, just below the frontal bone and in front of the occipital bone. This bone extends as wide as the skull and forms most of the base of the human skull.
Like the other bones of the skull, the sphenoid bone protects the structures of the brain and nerves. In addition, this spine also plays a role in supporting chewing and speaking.
6. Ethmoid Bone (Filter Bone)
The ethmoid bone is one of the most complex bones located between the eyes. These bones are about the size of an ice cube, light and spongy in shape, helping form the eye and nasal cavities.
The sinus cavities that are in the walls of the ethmoid bones also have important functions, including producing mucus to trap harmful allergens, calming the head, and regulating voice.
Structure or Parts of Facial Bones
Meanwhile, facial/facial bones are divided into 6 types, including:
The cheekbones or zygomatic bones lie just below the 2 eyes. This bone is shaped like a rectangle that extends up to the outside of the eye and down near the jaw.
The front of the cheekbones, which are thicker and serrated, serve as structures that hold the facial or facial bones together while protecting the arteries, nerves, veins, and organs that lie beneath the top of the skin.
The cheekbones are attached by several other facial bones, including the bones of the nose, jawbones, and the bones in front of the ears. The lower part of the cheekbones also plays a role in helping expression convoy. Meanwhile, the surface of the cheekbones connects the paras bone to the surface of the skull.
2. Maxillary bone
The maxilla consists of two pyramid-shaped maxillary bones that are fused in the middle. These two bones are located in the middle of the face which separates the nasal cavity and mouth. The maxillary bone contains the maxillary sinuses which are present on each side of the nose.
The jaw bones help define the shape of the face. In addition, this bone is where the upper teeth grow and creates the palate of expression & the lower part of the eye socket. That way, this bone also plays a major role in supporting the process of chewing and speaking.
3. Lacrimal Bone
The lacrimal bone is located in the eye socket. This rectangular shaped bone consists of 2 tops, one facing the nose and the other facing the eyes.
The lacrimal bone is part of the tear production system which forms the structure and supports the eye.
4. Nasal bones
Every human being has 2 nasal bones which are located in the upper middle of the face, to be precise between the forehead bones and the maxillary bones. This bone forms the bridge of the nose which is miniature and oval in size and shape, but can vary from person to person.
The nasal bones function to bind the cartilage that forms the contours of the human nose.
5. Lower jawbone
The mandible or mandible is the largest bone in the human skull. The shape of the lower jawbone consists of 2 parts, namely the horizontally curved part which forms the lower jaw line and the vertical which is connected in to the 2 sides of the body.
These bones form the lower part of the skull, lower tooth structure, & expression structures and use the upper jawbones. The lower jawbone can also help move expressions, such as chewing food.
6. Palatine bones
The palatine bones are the bones that help form the nasal cavities, under-eye cavities, and palate. This bone is in the shape of an L which is located at the bottom of the skull, precisely behind the maxillary bone and in front of the palate.
Clinically, these bones are home to the palatine nerves which function to give frequency of pain in teeth and expression.
The bones that make up the human skull on top are held together by connective tissue called “sutures”. These sutures are not fully fused when a baby is born. As we age, the gaps between the bones of the skull close and become stronger to protect the delicate brain structures.
By knowing the parts and functions of the skull bones, it is hoped that you will be able to provide more protection and attention to the parts of your head so that you avoid accidents that cause unwanted head injuries.
If there is a collision on the head that is relatively hard or there are complaints that may refer to disturbances in the brain, immediately consult the emergency room or the nearest doctor so that proper treatment can be given.
Abnormalities of the Skull Bones
There are several conditions or disorders that can threaten the integrity of the skull, such as:
1. Broken skull
Skull fractures can come in many types and degrees of severity. In some cases, the fracture is painless and heals on its own.
However, if it is classified as severe enough, you may need surgery to cure it.
The severity of skull damage varies depending on the force of the impact and the type of object that caused the injury, as well as the location of the head injury.
Here are some types of skull fractures (fractures) that can occur:
2. Closed Fracture
Closed fractures can occur when the bones of the skull are broken but the skin covering the bones is intact, with no cuts or open wounds.
3. Open fracture
Unlike closed fractures, open skull fractures result in damage to the skin at the fracture site. In fact, sometimes fractures are visible or appear from tears in the skin.
4. Fracture of the Base of the Skull
This type of damage occurs at the base of the skull or in the bones around the eyes, ears, or nose, or at the back of the skull near the spine. This injury often causes a meningeal tear and is one of the most fatal types of skull injuries.
5. Concave Fracture (sunken skull fracture)
This type of skull fracture occurs when part of the broken bone is pushed into the cavity of the brain and forms a concave shape.
Some babies are born with a condition called craniosynostosis, which involves premature closing of the sutures in the skull. This gives the skull an unusual shape and can sometimes influence facial features.
According to Johns Hopkins Medicine, craniosynostosis can cause an asymmetrical and abnormal shape of the skull or facial bones.
There are several types of cranial stenosis, depending on the affected suture, namely:
- Coronary synostosis: This type of baby may have a flat, raised forehead.
- Coronal synostosis: This type can flatten one side of the forehead and affect the shape of the eye sockets and nose.
- Lambdoid synostosis: This can cause flatness on one side of the back of the skull. It can also affect the position of the ears or cause the skull to tilt to one side.
- Metopic synostosis: This can result in a triangular shaped skull or a pointed forehead. It can also make the eyes appear closer.
- Sagittal synostosis: This disorder can accentuate the forehead. The area around it also seems narrow, giving the impression of an elongated head.
In its Clinical Review Article, the Department of Neurosurgery states that this condition can cause abnormal growth of the skull with severe craniofacial and cranial deformities.
If left untreated, other complications such as increased intracranial pressure and limited growth of the skull may occur.
Therefore, a person with craniosynostosis needs to be treated surgically to avoid complications in the future.
Apart from craniosynostosis, several other conditions that can affect the skull bones include:
7. Kleidocranial dysplasia
Cranial dysplasia is a mutation in a certain gene that causes abnormal development of the teeth and bones, including the skull. Common symptoms include a slanted forehead, extra bone at the skull joints, and an enlarged skull.
8. Craniometaphyseal dysplasia
This is an inherited condition that causes the bones of the skull to thicken causing the forehead to protrude and the eyes to open wide.
9. Paget’s Disease of Bone
New bone tissue is created quickly due to the abnormal activity of osteoclasts, which are a type of bone cell. People with this condition are more prone to fractures because the affected bones are usually weaker.
10. Fibrosa Dysplasia
This condition causes bone tissue to develop into scar tissue due to mutations in bone-forming cells. It tends to only affect one bone at a time, but can be involved in some cases.
11. Bone Tumors (Osteoma)
Osteoma is a benign growth of bone in the skull. People with bone tumors often have no symptoms.
However, if the growth presses on a nerve, it can cause hearing and vision problems. They usually heal after the tumor is removed.
Due to the importance of the functional parts of the skull, of course, it is necessary to maintain its health as well as possible.
One of the best ways to reduce the risk of falling, hitting or having an accident is to always wear a helmet when driving. Remember to always wear your seat belt while driving.
So a brief discussion about the meaning of the function of the skull bones. Not only understanding the meaning of the function of the skull bones but further discussing the parts of the skull bones and abnormalities found in the skull bones.
Knowing what the function of the skull bones is is very useful for someone to understand the various anatomy of the body and the role of the function of the skull bones in the human body. And, knowing the various possible diseases and disorders of the skull makes us more careful and maintains the condition of the body, especially the bones of our head.